POLYAMINE INVOLVEMENT IN MAMMARY CARCINOGENESIS

描述：本项目将重点研究多胺的激活作用。 生物合成和MAPK信号级联(通过致癌的ras或 HER-2neu)在乳腺癌发生中的作用。这些研究的基本原理是 由(1)曼尼博士提供的初步数据表明 多胺在乳腺癌发生中的作用，(2)显示的协同作用 几种恶性肿瘤模型中ras信号转导与多胺之间的关系 转化，(3)初步数据表明 HER-2neu信号与多胺在乳腺癌发生中的作用 申请人最近发现ODC过度表达会增加MAPK 乳腺上皮细胞的活性。此外，调查员将 检测功能性雌激素受体在卵巢癌中表达的重要性 RAS/HER-2neu和/或多胺介导的乳腺癌发生。他会的 在自然永生但不会致癌的 人乳腺上皮细胞株MCF-10A和HMT-3522。具体来说：(1) 他将确定鸟氨酸脱羧酶过度表达的影响 (ODC)(多胺生物合成中的第一个限速酶) 单独和结合激活MAPK级联(通过 Ras或HER2-neu)在体外和体内的转化特点。 (2)他将确定MAPK级联通路在介导 多胺和/或ras/HER-2neu介导的细胞转染效应 具有几种激酶的构成活性和显性负性突变 属于该信令级联(例如，RAF-1、MEK、ERK-1、ERK-2)。(3) 他将利用最近一代转ER的MCF-10A 和HMT-3522细胞株，表达功能性ER以检测可能的 恶性肿瘤患者激素信号与致癌信号之间的协同作用 人乳腺上皮细胞的转化。(4)他将评估 雌激素受体在转录水平上的“串扰” Ras/Her-2neu/多胺介导的信号转导途径及其相关研究进展 乳腺癌的发生。预计拟议的 实验将提供新的洞察力，使人们了解 雌激素与经典致癌信号在诱导中的协同作用 正常人乳腺上皮细胞的转化。

DESCRIPTION: This project will focus on the role of activation of polyamine biosynthesis and MAPK signaling cascade (by either oncogenic ras or HER-2neu) in breast cancer development. The rationale for these studies is provided by (1) Dr. Manni's preliminary data suggestive of a role for polyamines in mammary carcinogenesis, (2) the demonstrated cooperativity between ras signalling and polyamines in several models of malignant transformation, (3) the preliminary data showing cooperativity between HER-2neu signaling and polyamines in mammary carcinogenesis, and (4) the recent finding by the applicant that ODC overexpression increases MAPK activity in mammary epithelial cells. Furthermore, the investigator will test the importance of expression of a functional estrogen receptor in ras/HER-2neu and/or polyamine-mediated mammary carcinogenesis. He will conduct experiments in the spontaneously immortalized but non-tumorigenic MCF-10A and HMT-3522 human breast epithelial cell lines. Specifically: (1) He will determine the influence of overexpression of ornithine decarboxylase (ODC) (the first rate-limiting enzyme in polyamine biosynthesis) individually and in combination with activation of the MAPK cascade (by either ras or HER2-neu) on in vitro and in vivo features of transformation. (2) He will determine the role of the MAPK cascade pathway in mediating polyamines and/or ras/HER-2neu mediated effects by transfecting our cells with constitutively active and dominant negative mutants of several kinases belonging to this signalling cascade (e.g. Raf-1, MEK, ERK-1, ERK-2). (3) He will take advantage of the recent generation of ER transfected MCF-10A and HMT-3522 cell lines which express a functional ER to test the possible cooperativity between hormonal and oncogenic signals in the malignant transformation of human breast epithelial cells. (4) He will evaluate the "cross-talk" at the transcriptional level between the estrogen receptor pathway and ras/HER-2neu/ polyamine-mediated signaling as it relates to mammary carcinogenesis. It is anticipated that the results of the proposed experiments will provide new insights into the mechanisms subserving the cooperativity between estrogens and classic oncogenic signals in inducing transformation of normal human breast epithelial cells.